Inclined water tube boiler



July 25, 1950 H. D. COULBOURN 1 55 INCLINED WATER TUBE BOILER Filed March 26, 1945 4 Sheets-Sheet 1 INVENTOR. Hon 4E0 0. Combo ue/v WWW H. D. COULBOURN INCLINED WATER TUBE BOILER July 25, 1950 4 Sheets-Sheet 2 Filed March 26, 1945 INVENTOR. 5 H W/4E0 0 C004 50uz/v.

BY W Ms Arm e/vex H. p. COULBOURN mcumzn WATER TUBE BOILER July 25, 1950 4 Sheets-Sheet 5 Filed March 26, 1945 I lll INVENTOR. H n A20 Q COUL ISOUZN. BY

H. D. COULBOURN INCLINE!) WATER TUBE BOILER Jul 25, 1950 4 Sheets-Sheet 4 Filed March 26, 1945- INVENTOR.

W 0 w 0 w W Ms Arron/5K Patented July 25, 1950 INCLINED WATER TUBE BOILER Howard'D. Coulbourn, Wynnewood, Pa., assignor to Economic Heating Engineers, Wynnewood, Pa., a Declaration of Trustof Pennsylvania Application March 26, 1945, Serial No. 584,965

This invention relates to hot water heating boilers and is concerned primarily with boilers of the so-called horizontal tube type.

The art .of tubular boilers has been in existenceifor something over one hundred years, and most boilers which have been produced for many years past'have been designed in accordance with the accepted principles in this field, one of such principles is that if all of the tubes enter into a common header -the various currents counteract and interfere with one another and seriously impair the efiiciency of circulation. The Present invention proposes a boiler which is designed in substantially direct contradiction to this heretofore widely accepted theory.

One of the principal practical uses to which the boiler of this invention is intended to be applied is the heating of homes, apartments and similar building structures. In such heating installations efficient and efiective circulation of the heating medium, particularly hot water, is a highly important'factor. In such installations it has been generally recognized as necessary to employ a pump to achieve the required circulation. An important object of the present invention is the provision of a boiler which may be installed as an element of a heating system requiring circulation of hot water, but which eliminates the need of any mechanical device such as a pump, the circulation being efiected by the boiler itself.

Those skilled in the art of tubular steam boilers have long "recognized that the steam ordinarily generated by-the primary tubes of the boiler may be further heatedto provide super-heated steam. Such steam is, of course, of relatively high pressure, and when it'emerges from an orifice it has greatly increased velocity as compared to ordinary's'team. The present invention has as another object the provision of a tubular boiler which makes use of this principle as applied to hot water rather than steam. Thus when heat is applied-to water that has already been heated it 'will increase its velocity and afford improved circulatory effects.

In carrying out this idea in a practical embodiment the invention provides a boiler consisting generally of .spaced'headers, between which extend the boiler tubes. These tubes are inclined at an'angle in the neighborhood of fifteen degrees from the horizontal, with the header at the inlet side arranged lower'than the header at the out- 4 Claims. (Cl. 122-265) 1 above noted, in which the header at the outle tral chamber, a lower chamber, and an upper chamber. directly with the return side of the hot water heatingsystem, and this chamber is completely closed off from the lower chamber, which communicates only with the lowermost of the boiler tubes. The upper chamber communicates only with the uppermost of the'boilertubes.

A boiler designed in accordance with this invention also includes a drum disposed above the header assembly. The outlet header, which isthe uppermost, communicates directlywith one end of the drum, while the other end communicates with both the upperand lower chambers of the inlet header. Important objects and advantages of'the invention are associated with the particular structure which establishes thesecommunications. A further object of the invention isthe provision, in a -'tubul-ar boiler of the type noted, of a drum including a horizontal bafile,

disposedsubstantially central thereof, and which functions to retain the colder water in the drum and return it to the upper and lower sections of theinlet header. The "upper portion of the drum communicates with the outgoing or feeder side of "the hot water system.

"Still another object of the invention is the revision, in a tubular boiler of the type indicated, of a 'tube arrangement, which achieves maximum efliciency in deriving heat from the combustion'c'hamber therebeneath. In attaining this end, cir-cularheaders are employed, and these tubes are staggered, speaking with respect to the vertical, so that the upward path of the rising gases of combustion is rendered tortuous, thus high efilciency in heat transfer from these gases to the tubes is effected.

Another object of the invention is'the provision or a tubular boiler of the-character above noted, which includes refactory side walls, which are arranged closely to the tubular assembly. This forces the hot gases of combustion to pass through the tubular assembly rather than therearound. Other more detailed objects and advantages of the invention are associated with the The central chamber communicatesparticular construction and design of the refractory walls, and their relation to the other boiler elements.

In achieving the circulation of the hot Water of the heating system by the boiler alone, the lowermost tubes, which, it is to be remembered, are connected to the lower chamber of the inlet header and thus receive water that has been previously heated and returned from the drum, function as an injector, in that steam or super-heated steamfrom these lowermost tubes enters the outlet header, which is common to all the tubes and imparts upward momentum to the water therein. This momentum, coupled with the fact that the hot water tends to rise, causes the movement of the hot water up through the outgoing or feeder side of the heating system.

Various other more detailed objects and advantages of the invention, such as arise in connection with carrying out the above noted thoughts in a practical embodiment, will in part become apparent, and in part be hereinafter stated as the description of the invention proceeds.

The invention, therefore, comprises a boiler, which achieves the required circulation in a hot water heating system, with the complete elimination of a pump or other mechanical circulating device, by utilizing the injector principle of steam or super-heated steam, which is made possible by the particular construction and arrangement of the boiler elements.

For a full and more complete understanding of the invention, reference may be had to the following description and accompanying drawings, wherein:

Figure 1 is a perspective view of a tubular boiler designed in accordance with the precepts of this invention;

Figure 2 is a vertical section taken on a plane substantially midway between the side walls of the boiler;

Figure 3 is a sectional view taken on a plane normal to the showing of Figure 2, and looking from the rear or right-hand side of Figure 2; and

Figure 4 is a view similar to Figure 3, but taken looking from the front or left-hand side of Figure 2.

Referring now to the drawings, wherein like reference characters denote corresponding parts, the boiler of this invention is shown as comprising a front wall, which is referred to in its entirety by the reference character F, a rear wall designated generally R, side walls S, a, bottom B, and an arched top T. The lowermost portion of the front wall F is substantially vertical, this vertical portion being designated at It. Likewise, the lowermost part of the rear wall R is vertical, and this portion is identified at I l. The

receives the outlet header, which is referred to in its entirety by reference character H. The header H comprises a cylindrical member I 9, which is closed on the outer end by an end Wall 23, having a peripheral flange 2|, which serves as an anchorage in securing the header H within the front wall structure. The, header H also includes an inner circular wall 22, formed. with a large number of small circular tube openings 23.

The rear wall R, above the bottom vertical section II, is also inclined, and is substantially parallel to the section l8 of the front wall F. This inclined intermediate portion of the rear wall R. is designated 24. The part 24 is also formed with a circular opening, in which is fitted an inlet header, identified in its entirety by the reference character I. For a'clear understanding of the construction of the inlet header I, reference is had more particularly to Figures 2 and 3. The header I comprises a cylindrical wall 25, which is snugly fitted in the circular opening in rear Wall section 24, which is formed at the top with an opening 26, which communicates with an upwardly extending pipe 21, that may be formed integrally with the cylindrical member 25. Carried at the outer end of the cylindrical member 25 is a circular end wall 28, which is'formed with a central opening 29, in which is fitted one end of a pipe 30, that communicates with the return the openings 23 in the plate 22 of header H. The

openings in header plate 3! are also designated 23.

Arranged co-axially within the pipe section 21 is an inner pipe section 32, the walls of which are spaced from the walls of pipe section 21.

This pipe section 32 extends down within the inlet header I, and at its end carries an enlarged bell shaped structure 33, the circular walls of which are disposed within, and in spaced relation with respect to the cylindrical member 25. At the bottom, the member 33 carries a partition 34, which extends completely across the space between plates 28 and 31, and the outer or lower edge of the partition 34 is disposed beneath the W opening 29. This is important, as it prevents any bell shaped member 33 in a position in which its parts l0 and 11, together with the lower portion that gas may be conducted through the nozzle I1, and ignited within the combustion chamber l2 in a manner well known in this art.

Immediately above the vertical section ID, the front wall F includes an inclined central portion 18, which is formed with a, circular opening that outer or lowermost edge is disposed above the opening 29, thus an upper chamber 3'! is defined, and any direct communication between the inlet pipe 30 and the chamber 31 is inhibited by the partition 36.

Boiler tubes designated 38 extend between the corresponding openings 23 in the plates 22 and 3! in a well known manner. These tubes are preferably of small bore, and also will preferably be made of copper, because of the well recognized properties of this metal, which are desirable for this particular use. The tubes 38 are classified into three (3) groups: the lowermost tubes communicating with the lower chamber 35 of the inlet header I, the central tubes, which communicats with the inlet pipe 30 through the central chamber 39 of the inlet header I, and the uppermost tubes, which communicate with the upper chamber 31 of the inlet header I.

. Above the inclined wall section [8, the front wall includes the top vertical part 4.0, which is atlases formed with a circularopeni-ng' ll Therearwall R also includes a top vertical section 42, which is-f'ormed' with a circular opening 43, inalignment with the opening 4|. A drum, designated D, is fitted in the openings 41- and 43, and bridges the space between the front wall F, and the rear wall R.

The drum D comprises: a cylindrical wall 44, and end walls 45 and 46. At the bottom the cylindrical wall 44 is formed with a front opening 41 and a rear opening 48'. The cylindrical wall I9 is formed at the topwith an opening 49,. and

a pipe connection 50' establishes communications between the openings 41 and 49. This pipe connection 50- mayinclude the bolted flange structure illustrated. At the rear another pipe section 51, which may be integral with. the cylindrical wall 44, surrounds the opening 48 and is joined at the pipe section 21 by the bolted flange connection shown at 52.

Extending between the end walls 45 and 4B or the drum D is a bafiie 53, which, it will be noted, has downwardly inclined side flanges 54 that are spaced from the cylindrical wall 44. The purpose of this: bafiie will: be described when the op eration of the boiler is outlined in'detail.

The cylindrical wall 44- is formed with an upper opening 55, which communicates with a pipe 56 that is apart of the outgoing or feeder side of the hot water heating system. The pipe 56 will, of course, extend upwardly through the top T. The top T is also formed with another opening, which receives a Smokestack connection 51, which communicates between the upper space within the boileraround the drum-D, and a suitablepoint of exhaust for the spent gases of combustion.

Operation In outlining the operation of the above-dc scribed boiler, it will be assumed that the pipe section-56 is connected to the feeder side of a hot water heating system, and apipe section 3i! to the returning side. Also that there is a suitable source of gas, which may be thermostati cally controlled, which, by combustion in the chamber [2, results in hot gases passing upwardly between and around the tubes 38, during which period the tubes 38 extract heat from the gas, after which the gases pass around the drum D, and out the Smokestack connection 51. It will also be assumed there is an adequate supply ofwater' in the heating system, and, due to the influence of gravity, this water will, of course, completely fill the boiler elements comprising the. headers, tubes, drum and risers.

As: the water is first heated it passes upwardly from the outlet header H, through the riser 50, and into drum D. The baffle 53 will deflect the colder water and cause it to pass downwardly through the opening 48. It is evident that the.

the gases of combustion and, therefore, the hot-' test. This steam-water mixture is injected into the bottom of the header H. The injector action imparts momentum to the water in. the header H,

which causes it to move upwardly. The'upward. movement is further enhanced by the fact that. 75i;ta-kes less fuelto heat thissiven volume. of watex,.-.

the water is 'heated eud, under? the laws of thermodynamics; hot water will 1188" During thnseperiodsxwhen gas is being burned, the upper tubes and upper chamber 31. do not playany particularlyimportant part; However,

when the gas; is shut off and there. i no combustion-,.-the water from drum D will pass through the opening 48, and downwardly through. the: inner pipe section 32..into.- the. upper chamber 31, and 'then circulateback to the common header H. As: the boiler is continued in operation, only the hottest water .passes around the side flanges 54 of the baffie 53 and thence out through the opening 55, and pipe 56 Of the hot water system. As the hot water system functions in its normal manner, the cold water will seek its lower level, and be returned through the pipe section 30 to the inlet header I: It is particularly important to notethat asthe water comes from the pipe socion 30, itcannot pass directly into the lower chamber 35. It must first go through the central tubes whereby it is heated, thus pre-heated water is admitted into the lower tubes. This insures creation of the steam or super-heated steam, which is so essential to the operation Of this" boiler.

The operation of this boiler, which is predicated on the injector principle, is made possible by the fact that the motion imparted by a jet of steam to a surrounding column of water is sufficient to force it into a boiler from which the steam was taken. The steam escaping from under pressure has a much higher velocity than water would have under the same pressure and condition. The rate of speed at which steam travels, taken at an average boiler pressure of sixty pounds when discharged into the atmosphere, is about 1700 feet per second. When dischargedwith the full velocity developed by the boiler pressure through a pipe, the steam encounters the water in the common header. It is immediately condensed and its bulk will be reduced, say, one thousand times, but its velocity remains practically undiminished. Uniting with the body force has actually been derived from the boiler pressure itself.

The motive force of the injector is derived from the heat received from the steam. The steam is condensed and surrenders its latent heat, and

some of its sensible heat. The energy so given up by each pound of steam amounts to substantially 900 thermal units, each of which is equivalent to a mechanical force of Wil foot pounds. This would-be sufficient to raise a great many pounds of water against a very great pressure could it beso applied, but a large portion of it is used simply to heat the water raised. by the injector.

The particular arrangements of the tubes 38 illustrated. is of. particularv importance. Anest of tubes arranged in a horizontal circular position permits use of a greater number of tubes, and, consequently, greater heating surface exposed to the heating gases. This results in. more rapid heating of a given volume of water. Hence, it

It is notable that copper will absorb heat more quickly than iron or steel, and thus affords a quick transfer from the gases to the water or steam within the tubes.

.It is also notable that each horizontal layer of tubes is staggered ofi-center from the rows above and below it. This forces the gases to travel almost completely around each tube. The staggering of the tubes heats the tubes faster by retarding the flow of gases, and results in a lower stack temperature, and, consequently, saving of fuel.

The relation of the fire brick in the side walls S to the tube assembly is also of importance. The fire brick walls function as baflles which force thegases to pass up through the tubes. No heat is wasted passing outside the nest of tubes. The result is positive control heating and, consequent saving in fuel.

The arched construction of top T and its relation to the drum D is also of importance. Due to this construction and relation, whatever heat is left after passing through the tubes must surround the drum before being exhausted through the smokestack connection. The ultimate result of all these features of construction and design is that highly eflicient combustion is achieved. In fact, the degree of efiiciency of the boiler of this invention is not belived to have been achieved by known boiler constructions. Thus, a boiler of this design may be made as a very much smaller unit than would be the case of units of other design and like capacity.

In order to accommodate removal of the tubes and headers as a unit, each of the side walls S includes a pair of sections such as illustrated at 60 and (ii. Each of these sections 60 and 6! is hingedly mounted as shown at 62 so that either or both of them may be swung outwardly and afford access to the interior of the boiler. When this is done, the bolted flange connection 52 and that in the pipe section 50 may be disconnected.

The rear wall R. includes a removal panel as indicated at 63 which is held in assembled position by bolts 64. This panel is also removed and the connection of pipe section 36 to the hot water system broken, whereupon the whole unit of tubes 38, header H and inlet header I may be taken out as a unit. This is highly desirable from the servicing and repair viewpoint.

While a preferred specific embodiment of the invention is hereinbefore set forth, it is to be clearly understood that the invention is not to be limited to the exact construction illustrated and described, because various modifications of these details may be provided in putting the invention into practice within the purview of the appended claims.

What is claimed is:

1. In a tubular boiler, a nest of tubes inclined slightly from the horizontal, a common header at the upper end of said tubes, an inlet header at the lower end of said tubes, said inlet header ineluding spaced horizontal partitions defining upper, central and lower chambers, said upper chamber communicating with the uppermost of said tubes, the central chamber with the central tubes, and the lower chamber with the lowermost of said tubes, a drum above said tubes and headers, a riser connecting said common header communication between the other end ofv said drum and said lower chamber, means for establishing communication between said last mentioned end. of said drum and said upper chamber,

means for connecting the upper 'part of said drum to the feeder side of a hot water heating system, and means for connecting the return side,

of said hot water heating system to said central chamber.

2. In a hot water heating tubular boiler, a nest of tubes inclined slightly from the horizontal, a common header at the upper end of said tubes, an inlet header at the lower end of said tubes, said inlet header including horizontal partitions defining upper, central, and lower chambers, said upper chamber communicating with the uppermost of said tubes, the central chamber with the central tubes, and the lower chamber with the lowermost of said tubes, a drum above said tubes and headers, a riser connecting said common header and one end of said drum, means for establishing communication between the other end of said digum and said lower chamber, means for establishing communication between said last mentioned end of said drum and said upper chamber, means for connecting the upper part of said drum to the feeder side of a hot water heating system, and means for connecting the return side of said hot water heating system to said central chamber, said lowermost chamber connecting with the lowermost of said tubes, and means for applying the hottest gases of combustion directly to said lowermost tubes.

3. In a hot water heating system normally substantially filled with water, a tubular boiler, a nest of tubes inclined slightly from the horizontal, a common header at the upper end of said tubes, an inlet header at the lower end of said tubes, said inlet header including spaced horizontal partitions defining upper, central and lower chambers, said upper chamber communicating with the uppermost of said tubes, the central chamber with the central tubes, and the lower chamber with the lowermost of said tubes, a drum above said tubes and headers, a riser connecting said common header and one end of said drum, gravity means for establishing communication between the other end of said drum and said lower chamber, gravity means for establishing communication between said last mentioned end of said drum and said upper chamber, means for connecting the upper part of said drum to the feeder side of the hot water heating system, and means for connecting the return side of said hot water heating .system to. said central chamber exclusively.

4.- In. a tubular hot water heating boiler, a nest of tubes inclined slightly from the horizontal, and arranged in staggered relationship to provide a tortuous path for the heating gases, a common header at the upper end of said tubes, an inlet header atthe lower end of said tubes, said inlet header including spaced horizontal partitions defining upper, central and lower chambers, said upper chamber communicating with the uppe;- most of said tubes, the central chamber with the central tubes, and the lower chamber with the lowermost of said tubes, a drum above said tubes and headers, a riser connecting said common header and one end of said drum, means for establishing communication between the other end of said drum and said lower chamber, means (for establishing. communication between said, last mentioned end of said drum and saidupper and one end of said drum, means for establishing (5 h mb means for connecting. the upp part of said drum to the feeder side of a. hot water heating system, and means for connecting the return side of said hot water heating system to said central chamber, said drum containing a baflie having side edges spaced from the wall -5 thereof to permit passage of water therearound.

HOWARD D. COULBOURJN.

110 REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date Cooper Apr. 21, 1896 Stevens Dec. 20, 1898 Windham Aug. 1, 1899 Hornsby et a1. Dec. 24, 1901 Sims Aug. 3, 1909 Van Oosterwyck Nov. 29, 1921 Lose] Apr 6, 1926 Harter- Sept. 27, 1932 Firshing Oct. 25, 1938 Firshing July 29, 1941 Wiles et a1 Jan. 11, 1944 

